The following definitions apply throughout the specification, including in the claims:
“SATA standard” denotes the standard known as Serial ATA, Revision 1.0, adopted on Aug. 29, 2001, by the Serial ATA Working Group, for communication between a host and one or more storage devices over one or more serial links;
“SATA system” denotes a system including elements (sometimes referred to as “SATA components”) configured for communication over at least one serial link in compliance with the “SATA” standard;
“RAID” system denotes a system including at least one host (e.g., a CPU), at least two storage devices, and a controller (a RAID controller) coupled between the host and the storage devices to provide an interface between the host and the storage devices. Thus, the expression “RAID” system is used herein more broadly than in a conventional sense in which it denotes a system including at least one host, a “redundant array of inexpensive disks” (an array of inexpensive disk drives), and a controller coupled between the host and disk drives to provide an interface between the host and disk drives;
a “swaged” element denotes that the element is shaped for deforming another element into a complementary shape. For example, a “swaged” cam herein denotes a cam shaped and configured to be capable of deforming another element into a shape complementary to the cam's shape (e.g., temporarily deforming a flexible element into the complementary shape such that the flexible element can later move or be moved back into its original shape); and
“enclosure” (for one or more storage devices) denotes a structure in which each storage device can be removably secured. The term “enclosure” is used broadly to denote either a structure that can enclose a storage device completely (on all sides) or a structure that does not completely enclose a storage device.
The expressions “storage devices” and “storage components” are used interchangeably herein (as synonyms).
The expressions “assembly” and “apparatus” are used interchangeably herein (as synonyms). It is not intended that an “assembly” or “apparatus” necessarily consists of discrete structures that are assembled together to manufacture it.
Banks, hospitals, government institutions, public institutions and similar entities often employ multi-storage component systems to manage their data. Due to the importance of the data, data loss (e.g., due to a hard disk drive failure) cannot be tolerated. In some conventional systems for managing data in a multi-storage component environment, a RAID controller manages data transmission over a serial link between multiple storage units and a host server (e.g., a personal computer). In FIG. 1 (an example of such a system), each of RAID controllers 30 includes a host connection 40 which is configured to be coupled to a host (not shown in FIG. 1) via a serial link. In various implementations of the FIG. 1 system, host connection 40 can be implemented to be compatible with any of several different types of serial links, including SCSI (small computer system interface), fibre channel, ethernet, and firewire (IEEE standard 1394) links. Each RAID controller 30, which can be implemented as a commercially available RAID controller (e.g., one available from CMD Technology Inc. of Irvine, Calif.), performs a multiplexing function to distribute data over several storage components (e.g., in a striping arrangement). If one storage component fails to function properly, a RAID controller 30 prevents the loss of data stored on the failed storage component.
In the FIG. 1 system, each RAID controller 30 can be coupled to two (or more) storage components 60, and each storage component 60 is coupled to one of power supplies 50. More specifically, each of RAID controllers 30, storage components 60, and power supplies 50 is connected to backplane 55 (sometimes referred to as a “midplane”), and backplane 50 provides the appropriate connections between components 60 and RAID controller 30 and between components 60 and power supplies 50. Typically, host connection 40 is a SCSI or fibre channel type connection since such a connection allows multiple storage components to be connected to a host server 20: up to 125 storage components for fibre channel and up to 14 storage components in the case of SCSI.
While the SCSI and fibre channel standards support multi-storage system environments, the associated SCSI and fibre channel storage components are four to six times more expensive than the traditional IDE (integrated device electronics) storage components that are used in most PC's. The IDE standard only supports the connection of two IDE storage components, however, and is therefore not ideal for use in a multi-storage component environment.
SATA systems have been developed as a next generation standard replacement for IDE. SATA storage components are similar in cost to IDE storage components. However, the SATA standard requires tight impedance control for on board signal routes and as a result SATA storage components cannot simply be plugged into a circuit board substrate due to potential distortion. Due to their low cost, it is desirable to use SATA storage components in a multi-storage component environment. U.S. Pat. No. 6,843,674, issued Jan. 18, 2005, describes a cable (having a connector configured to be coupled to a complementary connector of a SATA component) and other hardware for connecting SATA storage components to other components in a multi-storage environment.
SATA connectors (for connecting SATA storage components to other components such as controllers and power supplies) have many desirable characteristics including the following: a SATA connector has a low pin count, supports lower operating voltages and higher data transfer rates than IDE, and can be used with very thin and flexible cables.
Among the disadvantages and limitations of conventional systems that include a backplane (e.g., backplane 55 of FIG. 1) for connecting storage devices to other elements are that a backplane typically is undesirably bulky, and since component location is fixed due to the use of plug-in boards with a backplane, system design is constrained.
To eliminate such disadvantages and limitations, it would be desirable to implement a system in which SATA storage components (or other storage components) are connected in a multi-storage component environment without the use of plug-in boards or a backplane.
A system of this type is described in above-cited U.S. Pat. No. 6,843,674. A system very similar to the one described in U.S. Pat. No. 6,843,674 will next be described with reference to FIGS. 2 and 3.
The system of FIGS. 2 and 3 includes SATA storage components 80 (which can be disk drives), and chassis 100 having bays 90 for receiving the components 80. At the end of each bay 90, chassis 100 has an opening 110 into which one end of a SATA cable 120 and to one end of a power cable 150 (or a specialized connector coupled to one end of a SATA cable 120 and one end of a power cable 150) can be inserted so that the SATA and power cables (or specialized connector) can be coupled to a complementary connector of a component 80 in the bay 90. The other end of each such SATA cable 120 plugs into an appropriate connector of RAID controller 130, and the other end of each such power cable 150 plugs into power supply 140. RAID controller 130 includes a host connection 160 which is configured to be coupled to a serial link (e.g., serial link 161 of FIG. 3) to allow communication via the serial link between controller 130 and a host (e.g., host computer 20 of FIG. 3). RAID controller 130 regulates the flow of data between the host and each of the SATA storage components 80 via the serial link (to the host) and cables 120. Host connection 160 can be implemented to be compatible with any of several different types of serial links, including SCSI (small computer system interface), fibre channel, ethernet, and firewire (IEEE standard 1394) links.
RAID controller 130 also includes a SATA connector 80A (shown in FIGS. 2 and 3) for each of bays 90. One end of each of the SATA cables 120 can be coupled to each of SATA connectors 80A. Data from host 20 propagates over serial link 161 to host connection 160, and from host connection 160 to input buffer 170 of RAID controller 130. The data are distributed to SATA storage components 80 via data distribution component 180 of RAID controller 130. As will be apparent to those of ordinary skill in the art, input buffer 170 can be a standard, high impedance input buffer and distribution component 180 can be implemented to include at least one multiplexer, electronic switch, or similar device.
It would be desirable to removably secure storage components 80 in chassis 100 of FIG. 2, so that each storage component can be locked into a position with its SATA and power connector aligned with slot 110 so that the storage component can be coupled to SATA and power cables (or to a connector coupled to such cables) and then decoupled from the cables (or connector) when desired, and so that the storage component can be unlocked and removed from the chassis (after being decoupled from the cables or connector). More generally, it would be desirable to removably secure storage components (e.g., SATA storage devices) in a chassis or other enclosure (using simple, inexpensive hardware, and without the need to mount any of the storage components in or to an individual disk carrier or other carrier), so that each storage component can be locked into a position for convenient coupling to a connector (e.g., a connector of or coupled to a SATA cable or other serial link) and then decoupling from the connector, and so that each storage component can be unlocked and removed from the enclosure (after being decoupled from the connector).